Templatize AstVisitor with its subclass

src/parsing/preparser.h

Index: src/parsing/preparser.h
diff --git a/src/parsing/preparser.h b/src/parsing/preparser.h
index 46835cafb9e4b5503d88438fb6222d532d65acc5..914e64c988d61c82beed4ed0d0bbccb0fdaf9eb5 100644
--- a/src/parsing/preparser.h
+++ b/src/parsing/preparser.h
@@ -802,15 +802,14 @@ class PreParserTraits {
     return PreParserExpression::This();
   }
 
-  static PreParserExpression SuperPropertyReference(Scope* scope,
-                                                    PreParserFactory* factory,
-                                                    int pos) {
+  static PreParserExpression NewSuperPropertyReference(
+      Scope* scope, PreParserFactory* factory, int pos) {
     return PreParserExpression::Default();
   }
 
-  static PreParserExpression SuperCallReference(Scope* scope,
-                                                PreParserFactory* factory,
-                                                int pos) {
+  static PreParserExpression NewSuperCallReference(Scope* scope,
+                                                   PreParserFactory* factory,
+                                                   int pos) {
     return PreParserExpression::SuperCallReference();
   }